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Are you monitoring the correct fuel pressure parameter? There's like two of three of them. It should be the one that says Fuel Pressure Direct Injection.

OK I was reading the wrong fuel pressure param. Yeah, DH is reading the Fuel Pressure as stated above.

May be we should create a sticky thread for the parameters, their meaning and what should be they OK values to point out to newbes like me what are import and on what to focus when starting messing arround with their car.

This is the last question about login. Knock retard with DH: Which PID parameters read it and what should be the OK value?

i only have sri, testpipe, ets tmic but in the cold...while getting on it a little bit...it just didnt feel right. now theres no hiccups.

Yea man, mine felt like it was slightly surging (aka fuel pressure drop) but I thought it was just the shitty stock tune. NOT.

Originally Posted by Mchart

My FRP drops to 1100 at WOT around near where max torque is on the band. I have nothing but a tune.

So i'd be careful even putting an intake on this car considering that people like me are maxing the pump out with nothing but a tune.

That said, I don't see this being an issue in terms of hurting the engine. If the ECM realizes it can't supply the fuel it needs it will drop boost to save the engine. If things get really bad it will outright cut load. So really, the worst that is happening is that you are loosing power.

Really sucks that Mazda didn't put a more robust pump in though. In really cold temps I could see the FRP dropping even on the stock tune.

Its not the pump to blame really. Christian himself has mentioned that the gen2 pump is slightly better than the gen1's. Its the ecu logic that screws it up by its over reactive fuel dumping at the slightest pressure drop. Hopefully they can find away around it's illogical dumping, or else a hpfp or internals might as well be your first mod.

While it is an issue - I would rather it have go apeshit and want to dump fuel then the other way around and let things get to lean. As stated, i've yet to see the AFR's change when this is happening. So I beleive it is at least keeping things safe, but we are loosing power becuase of it.

if i had to do it over again, the first thing i would do is hpfp (either internals or the cp-e) and next, the AP.
IMO, spending the $300.00 on the internals and $600.00 on the AP will give you much better performance, while maintaining safety, than any other combination of bolt ons.

When it starts dumping fuel, it over loads the fuel system causing the pressure to drop which is much more dangerous. Understand?

Dangerous probably for the pump. Again, i've seen no indication on my logs that this would be dangerous for the engine. The AFR's stay exactly where they are supposed to be. If the AFR's aren't changing I fail to see how this would be dangerous for the engine itself. Probably ain't good for the fueling system though.

If your pump fails while going wot due to the ecu over stressing it, you could run very lean and blow if the ecu does not cut the power soon enough. Then again, who here wants to be dropping money on replacing their stock pump? Doubt it's a cheap item at the dealership.

If your pump fails while going wot due to the ecu over stressing it, you could run very lean and blow if the ecu does not cut the power soon enough. Then again, who here wants to be dropping money on replacing their stock pump? Doubt it's a cheap item at the dealership.

I agree with you there.

I'm just pointing out that it isn't doing any damage unless the pump outright fails and stops providing fuel. Even then, i'd think the ECM would be able to prevent catostrophic failure though.

I don't know if you're trying to make yourself feel better about worrying about the issue and just placing your faith in the ecu to prevent failure. The ecu will most likely prevent total failure of the engine, but it won't prevent your fuel pump from living a short life. As more and more gen2's get modded more extensively and tuned, we will probably start seeing more pump failures.

Point is, monitor you fuel pressure. A Dashdaq or similar should be your first or 2nd mod on the gen2. As I already pointed out, I saw pressure drop with only two airflow mods.

I don't know if you're trying to make yourself feel better about worrying about the issue and just placing your faith in the ecu to prevent failure. The ecu will most likely prevent total failure of the engine, but it won't prevent your fuel pump from living a short life. As more and more gen2's get modded more extensively and tuned, we will probably start seeing more pump failures.

Point is, monitor you fuel pressure. A Dashdaq or similar should be your first or 2nd mod on the gen2. As I already pointed out, I saw pressure drop with only two airflow mods.

And seriously, why risk it?

^^^This.

Mchart, instead of throwing caution to the wind with your 22k car, wouldn't you rather spend the 300-600 on a fuel pump to make sure your car a) runs safely and b) can make actual use of the mods you add? I've ridden with/raced Amazon, his car bogs like a mofo with a tp and cai for power mods, that's it. Now for the first time he can finally monitor it with his AP and it is dangerously low in some instances. Not worth the risk imho, and they are real risks. Apparently you can monitor mchart, most guys can't. Bottom line, like Nataphen said, make sure you can monitor and see what your exact set up is doing.

Apparently you don't know my history. I'm one of the people who has presented the issue. I'm just pointing out the valid fact that the engine isn't going to be 'hurt' if the AFR's remain where they are at.

As you read in my posts, I constantly datalog my car. Otherwise, I wouldn't say what I have been saying. My AFR's stay where they should be, even when the pressure drops to 1100 PSI. Yes, I am getting a pump; As you may or may not know obtaining a pump is near impossible right now. I would have gotten one over a month ago - But everyone has been out of stock.

I am not telling people to not get a pump. I am simply pointing out the fact that engine damage will not occur unless the pump outright locks up, and/or your AFR's reflect an over-lean condition.

Your approach does not inspire confidence in what knowledge you have concerning this issue. The pumps have failed on gen1's before. You say the car won't be hurt "if" the afr's stay where they should? No thanks, I'll not go wot again until my hpfp comes in, plain and simple. My car cuts more and more now and I don't want to be like doubleflusher and have to limp around on 742 psi for weeks or months until I get a pump or internals in.

char181, I don't see any validity in you groaning Nazarite's post, please explain.

Well, doesn't the intake/racepipe combo raise boost? I thought corksport said boost went to about 18psi.

I'm a Gen 1 guy, so what I'm about to say may not apply if the Gen 2 ECU is radically different in the way it deals with drop in fuel pressure. But, above quote is consistent with my experience. On stock tune with just a CAI and a catless dp/rp into stock CBE I was seeing about a 2 psi increase in boost over stock before my tune. I'm still on stock fuel pump at 47,000 miles, but keep fingers crossed.

It seems from the datalogging experience of gen 1 users who did have fuel pump pressure drops that the gen 1 ECU does pull timing and sacrifice boost and other engine operating parameters to focus on maintaining safe AFR's when the pump shits. I don't know if this is the case with gen 2. Datalogging would be necessary to find out if the newer ECU works the same way to maintain safe AFR's.

Your approach does not inspire confidence in what knowledge you have concerning this issue. The pumps have failed on gen1's before. You say the car won't be hurt "if" the afr's stay where they should? No thanks, I'll not go wot again until my hpfp comes in, plain and simple. My car cuts more and more now and I don't want to be like doubleflusher and have to limp around on 742 psi for weeks or months until I get a pump or internals in.

char181, I don't see any validity in you groaning Nazarite's post, please explain.

I don't understand why you want to have a shitfit over my post. My post isn't wrong. Nor am I suggesting that people not buy a pump. Not everyone can get a pump right now. Not everyone is getting fuel cut either. To say it isn't safe to drive around might be the case on your car. In my case I didn't even have pressure drop until it got a lot colder outside. Nor do I have drop at all unless I floor it. I have 3 and half months worth of datalogs from every time the car has been turned on. Most days I don't even WOT the car. Thus, i'm not going to stop driving my car due to the pump not putting out at WOT when it is really cold outside. Even when the pressure did drop, as i've stated, the AFR stayed at approx. 11.2 (Which is what it has been tuned to). Thankfully, i've finally found a pump and i'm getting it installed this weekend. That said, I wasn't going to stop driving my car because of it.

I'm a Gen 1 guy, so what I'm about to say may not apply if the Gen 2 ECU is radically different in the way it deals with drop in fuel pressure. But, above quote is consistent with my experience. On stock tune with just a CAI and a catless dp/rp into stock CBE I was seeing about a 2 psi increase in boost over stock before my tune. I'm still on stock fuel pump at 47,000 miles, but keep fingers crossed.

It seems from the datalogging experience of gen 1 users who did have fuel pump pressure drops that the gen 1 ECU does pull timing and sacrifice boost and other engine operating parameters to focus on maintaining safe AFR's when the pump shits. I don't know if this is the case with gen 2. Datalogging would be necessary to find out if the newer ECU works the same way to maintain safe AFR's.

From the data i've recorded on my car the Gen 2 ECM does indeed pull boost when the pump drops pressure. I've never had fuel cut, so I haven't been able to look at any logs to see what happens when that happens.

In my case, temps below approx. 58 degrees F at WOT is when the the fuel pressure drops. Boost is set to around 19PSI, and the instant the pressure drops boost is dropped to around 17 PSI where it then stays steady until the RPM's get higher and the pump has less issues. So cobb's findings of approx 18 PSI being the 'max' before the pump has issues fits in line with the data i've seen from my own car.

While it is an issue - I would rather it have go apeshit and want to dump fuel then the other way around and let things get to lean. As stated, i've yet to see the AFR's change when this is happening. So I beleive it is at least keeping things safe, but we are loosing power becuase of it.

.. But i'd rather loose power then cause engine damage.

Just because your AFR isn't changing doesn't mean you're getting quality combustion when fuel pressure drops. Remember since IPW goes up when FP drops your O2 sensor will see the correct amount of fuel, however that fuel was not properly atomized (since FP dropped so low) and the inherent cooling effect of a properly atomized direct injection cycle can be lost and you are then more prone to knock despite everything looking good on your AFR's.

Bottom line IMHO, on a Gen 2 in order to minimize risk from widely varying stock pump capabilities a HPFP should be the first upgrade before anything else is done. A lot of people justify waiting on a pump not only because they might be one of the lucky ones that have a good stock pump but because it isn't a flashy go-fast part and doesn't make cool noises so they feel money is better spent elsewhere much like when people with only an SRI go buy a bling-tastic BOV/BPV.

Again some of this is my opinion and conjecture but it comes from my experience as an alphatester and asking questions/learning from Christian. He is welcome to chime in if something I said is completely baseless. It's hard to understand why someone would even remotely risk blowing a motor to save $300-600 when they happily drop that much and more on SRI's, DP's, FMIC, etc.

Just because your AFR isn't changing doesn't mean you're getting quality combustion when fuel pressure drops. Remember since IPW goes up when FP drops your O2 sensor will see the correct amount of fuel, however that fuel was not properly atomized (since FP dropped so low) and the inherent cooling effect of a properly atomized direct injection cycle can be lost and you are then more prone to knock despite everything looking good on your AFR's.

Bottom line IMHO, on a Gen 2 in order to minimize risk from widely varying stock pump capabilities a HPFP should be the first upgrade before anything else is done. A lot of people justify waiting on a pump not only because they might be one of the lucky ones that have a good stock pump but because it isn't a flashy go-fast part and doesn't make cool noises so they feel money is better spent elsewhere much like when people with only an SRI go buy a bling-tastic BOV/BPV.

Again some of this is my opinion and conjecture but it comes from my experience as an alphatester and asking questions/learning from Christian. He is welcome to chime in if something I said is completely baseless. It's hard to understand why someone would even remotely risk blowing a motor to save $300-600 when they happily drop that much and more on SRI's, DP's, FMIC, etc.

Not disagreeing at all. I was just pointing out that many of us can't even find/buy a damn pump upgrade right now; So storing the car until you get one seems a little over kill. Don't floor the car and most should be fine until they get the pump.

In no way am I suggesting that people should go out and WOT the fucker like normal just because the datalogs haven't shown any AFR issues.

Not disagreeing at all. I was just pointing out that many of us can't even find/buy a damn pump upgrade right now; So storing the car until you get one seems a little over kill. Don't floor the car and most should be fine until they get the pump.

In no way am I suggesting that people should go out and WOT the fucker like normal just because the datalogs haven't shown any AFR issues.

I know, I wasn't calling you out for your advice or anything your post was just the easiest to piggyback from and explain the AFR/FP side of things. I just don't want everyone to think just because their AFR numbers look good they can ignore the fuel pressure drop, the issue is just not that simple.

RPM had a few CP-E pumps still in stock when I bought mine 3 weeks ago, did they get cleaned out as well in the great 2011 HPFP shortage!

I know, I wasn't calling you out for your advice or anything your post was just the easiest to piggyback from and explain the AFR/FP side of things. I just don't want everyone to think just because their AFR numbers look good they can ignore the fuel pressure drop, the issue is just not that simple.

RPM had a few CP-E pumps still in stock when I bought mine 3 weeks ago, did they get cleaned out as well in the great 2011 HPFP shortage!

About 5 days ago they had 1 left when I called, but i've decided to get the KMD internals and have Joe install them on Saturday.

With Gen1 cars there was a strong correlation between blown engines and overworked pumps - especially as the temperatures dropped.

The Gen1 car adds fuel when it registers a certain amount of knock. This addition of fuel usually causes a drop in the fuel pressure if the pump is at the limit. Lower pressure is bad for several reasons regardless of the commanded injector pulsewidth:

1. Lower pressure means poorer atomization of the fuel and less contribution of that fuel to combustion

2. The fuel pressures combat cylinder pressures in direct injected applications. The drop in pressure becomes even more of a concern than it would in a PI vehicle since the PW has to make up for a lot of headroom as the injected pressures get close to the cylinder pressures.

3. The injection time in DI cars is half of what it is in PI vehicles

Overall, ensuring you are maintaining as designed DI fuel pressures is essential and combustion efficiency and safety - especially at WOT and in times of high air density (cold temps) - when the pumps show their weaknesses.

^ Excellent explanation. At least the Gen 1 ECU was trying to protect AFR at the expense of other parameters. Indeed, that does and did not guarantee protection from zoom, zoom, boom. But it was better than letting the engine truly lean out.

Thanks for the more technically correct detail on what was happening and the possibly hidden risks of relying just on protected AFR's.

I think I'll now get on the list for an upgraded pump, even though I've been one of the lucky ones not to see a drop in pressure (so far)!

^ Excellent explanation. At least the Gen 1 ECU was trying to protect AFR at the expense of other parameters. Indeed, that does and did not guarantee protection from zoom, zoom, boom. But it was better than letting the engine truly lean out.

Thanks for the more technically correct detail on what was happening and the possibly hidden risks of relying just on protected AFR's.

I think I'll now get on the list for an upgraded pump, even though I've been one of the lucky ones not to see a drop in pressure (so far)!

The Gen 2 ECM seems to protecting AFR as well, as the logs have shown. This includes doing things like dropping boost, among other things. I would assume with the way the Gen 2 ECM operates is that it is playing things far safer then the Gen 1 ECM ever did.

I don't understand why you want to have a shitfit over my post. My post isn't wrong. Nor am I suggesting that people not buy a pump. Not everyone can get a pump right now. Not everyone is getting fuel cut either. To say it isn't safe to drive around might be the case on your car. In my case I didn't even have pressure drop until it got a lot colder outside. Nor do I have drop at all unless I floor it. I have 3 and half months worth of datalogs from every time the car has been turned on. Most days I don't even WOT the car. Thus, i'm not going to stop driving my car due to the pump not putting out at WOT when it is really cold outside. Even when the pressure did drop, as i've stated, the AFR stayed at approx. 11.2 (Which is what it has been tuned to). Thankfully, i've finally found a pump and i'm getting it installed this weekend. That said, I wasn't going to stop driving my car because of it.

Not everything is so black and white.

Originally Posted by Lex

With Gen1 cars there was a strong correlation between blown engines and overworked pumps - especially as the temperatures dropped.

See, I've been around this platform for 3 years now, every time the weather gets colder we have several Mazdaspeed's blow without fail. This is where I'm coming from on this matter.

I wasn't having a fit over your post, nor did I ever call it wrong. I merely said it did not give one confidence in your knowledge concerning this issue. I don't think we have quite put our finger on what causes the MS3 to blow, but I'm gong to bet the fuel pump and high loads at low rpm's played a significant roll. I don't know what your mods are, but on mine, even though its not outright "fuel cut", it definitely surges in and out. This is the first winter for most gen2's, and many of them aren't very modded yet. I'm sure next winter we'll see the record become tarnished to a degree.

See, I've been around this platform for 3 years now, every time the weather gets colder we have several Mazdaspeed's blow without fail. This is where I'm coming from on this matter.

I wasn't having a fit over your post, nor did I ever call it wrong. I merely said it did not give one confidence in your knowledge concerning this issue. I don't think we have quite put our finger on what causes the MS3 to blow, but I'm gong to bet the fuel pump and high loads at low rpm's played a significant roll. I don't know what your mods are, but on mine, even though its not outright "fuel cut", it definitely surges in and out. This is the first winter for most gen2's, and many of them aren't very modded yet. I'm sure next winter we'll see the record become tarnished to a degree.

I'm well aware. That said, the vast amount of cars in the blown engine thread here blew because the driver was doing some stupid shit and/or they did stupid shit like put on a BOV. I've seen a few that have blown for no apparent reason other then maybe fuel pressure.. But even then, I haven't found any threads on this site showing datalogs that a person was running low pressure, and then their engine popped.

I think there is maybe 1 thread on here that I know of where someone actually was doing data logs before he blew and it seems to have correlated to low FRP. He was well below even 1100 PSI if I recall though.

Not saying it isn't the cause of a bunch of blown engines, but at the same time we don't exactly have much data to support the assumption either way though.

I could very well be wrong. As I said though, at least from what i've seen in the blown engine thread.. Most blown engines didn't even happen at WOT. Which would not indicate a drop in fuel pressure.

As i've said; Nothing but a tune. Above 60 degrees the pump remains above 1600 PSI. Below that and the pump starts to drop in the part of the rev band where max torque is made at which point the ECM drops boost to a level the pump can sustain (around 17PSI) and after around 4500 RPM's the pump shoots back up to 1700 PSI. At this point the boost is set to taper off to around 17-18 PSI anyways though. (From what I can gather) So as it is, i'm loosing some power in colder weather at WOT right now. Which is why i'm not very concerned in regards to my own car. (well, i'd lie to say i'm not worried. I am. That said, if I stay off the throttle I have nothing to worry about.)

Please note that i'm not an expert by any means. I'm just relaying what i've seen over the past few months of data logging.

the problem is there are no good dataloggers for the gen 2. You can get a dashdaq for the same price price as the AP. Does anyone know if a dashhawk will show fuel pressure, fuel trims? Does the dashhawk competely not work with the gen 2 or does it work choppy or not show all the data like knock and afrs?

No, infact there are several very good, fairly priced, solutions to the monitor issue;
We have been selling and pushing the Innovate motorsports datlogers for YEARS. These are robust as hell, log at a very high sample rate, and are easy as hell to use for the average modder.
Most profesional tuning shops have two or three LM-2s they use to log cars while on the dyno. These are the best logers short of a full blown Motec setup!

The OT-2 is a downsized unit that does everything the LM-2 does, less the stand alone wideband, and display, and works wirelessly with your laptop, Iphone, Ipad,or Ipod touch.

The software that Innovate uses is self graphing, and very addaptive.

We have a ton of the OT2's on the shelf right now. Retail price is dirt cheap at 179.95 If you guys without a way to monitor your car want them, drop me a line, I'll give you a great GB on the little suckers

I was seeing sub 1100 PSI with an SRI, TIH, BPV & a tune. I upgraded the internals and all seems kosher even in the 20 degree weather. Again, no reason to test WOT at this point as it is too cold and there is 1FT of snow on the ground. My pressure would drop the second the ECU would get Knock, thus dumping fuel to compensate. All the logs from the AP show pressure is holding firm above 1500 PSI even in higher RPMs. I am now 1 week with the internals installed and will give updates or can post logs of pre-pump upgrade vs now if anyone is interested.

I was seeing sub 1100 PSI with an SRI, TIH, BPV & a tune. I upgraded the internals and all seems kosher even in the 20 degree weather. Again, no reason to test WOT at this point as it is too cold and there is 1FT of snow on the ground. My pressure would drop the second the ECU would get Knock, thus dumping fuel to compensate. All the logs from the AP show pressure is holding firm above 1500 PSI even in higher RPMs. I am now 1 week with the internals installed and will give updates or can post logs of pre-pump upgrade vs now if anyone is interested.

I'm sorry, but I've heard it brought up a couple of times in this thread, what is so bad abou pt going WOT in cold temperatures if you have logs and everything is kosher on them?

If your logs are fine, your car should be fine. I think that people are just saying that colder temps are when the pump gets stressed more, i.e. FRP is fine above 60* temps, but colder than that it starts to drop. If your logs are OK, you shouldn't have to worry.